Method and apparatus for removing cylinder liners of automotive vehicle diesel engines

ABSTRACT

Cylinder liners are removed or extracted from diesel engines of automotive vehicles, with the diesel engine remaining mounted on the vehicle, by removing only the pistons, piston rods and the bolts holding the main bearing caps and rotating the crank shaft so that the cranks extend horizontally. The main bearing cap bolts are utilized to secure, to the undersurfaces of the main bearing caps in depending relation therefrom, a pair of substantially identical angle brackets having aligned apertures at their lower ends. A cross bar is inserted through these apertures, and a pressing tool is placed in the lower end of the cylinder liner and secured by a threaded bolt and nut to a centering device seated in the upper end of the liner. An ordinary shop jack is then positioned on the cross bar in engagement with the pressing tool, and is extended to push the cylinder liner upwardly out of the cylinder.

United States Patent Hodge 1 1 Aug. 22, 1972 1 41 METHOD AND APPARATUSFOR 2,741,022 4/1956 Weaver ..29/280 x REMOVING CYLINDER LINERS OF2,909,210 10/1959 Bennett .29/255 x AUTOMOTIVE VEHICLE DIESEL ENGINESPrimary Examiner-Wayne A. Morse, Jr. Attorney-McGlew and Toren [5 7]ABSTRACT Cylinder liners are removed or extracted from diesel engines ofautomotive vehicles, with the diesel engine remaining mounted on thevehicle, by removing only the pistons, piston rods and the bolts holdingthe main bearing caps and rotating the crank shaft so that the cranksextend horizontally. The main bearing cap bolts are utilized to secure,to the undersurfaces of the main bearing caps in depending relationtherefrom, a pair of substantially identical angle brackets havingaligned apertures at their lower ends. A cross bar is inserted throughthese apertures, and a pressing tool is placed in the lower end of thecylinder liner and secured by a threaded bolt and nut to a centeringdevice seated in the upper end of the liner. An ordinary shop jack isthen positioned on the cross bar in engagement with the pressing tool,and is extended to push the cylinder liner upwardly out of the cylinder.

10 Claims, 6 Drawing Figures METHOD AND APPARATUS FOR REMOVING CYLINDERLINERS OF AUTOMOTIVE VEHICLE DIESEL ENGINES BACKGROUND OF THE INVENTIONAs presently used in trucks, buses and the like, diesel engines are soinstalled, as beneath the cab, that there is, on top of the engine, onlyenough clearance to allow removal of the cylinder liners or sleeves.There is no extra clearance for a sleeve puller or extractor, and thisis true irrespective of whether the cylinders are vertical, at 45, or at60. Accordingly, in order to extract or pull the cylinder liners fromthe engine block, it is necessary to dismount the entire engine from thevehicle and then to position a cylinder extracting arrangement on top ofthe engine to pull a cylinder liner upwardly out of a cylinder. 'A linerreplacement operation thus involves a large amount number'of man hoursof work, to dismount-the engine from the vehicle, to extract thecylinder liners, to replace new or reconditioned cylinder liners in theengine, to reassemblethe engine, and to re-mount the engine in thevehicle. In cffect, replacing a cylinder liner becomes a major and timeconsuming operation.

SUMMARY OF THE INVENTION This invention relates to the removal andreplacement of cylinder liners of diesel engines driving automotivevehicles and, more particularly, to an improved, simplified and moreefficient method and apparatus for removing and replacing the cylinderliners.

In accordance with the invention, cylinder liners are removed fromautomotive vehicle diesel engines while the engines remain in thevehicles. This is effected by pushing the cylinder liners upwardly outof the cylinders, operating from beneath the engine, as contrasted tothe known practice of pulling the cylinder liners upwardly out of thecylinders, after the engine has been dismounted from the vehicle, andoperating from above the engine.

More specifically, in practicing the method of the invention and whilethe diesel engine remains in mounted position on the vehicle, a cylinderhead is removed, a piston and its piston rod are pulled and the crankshaft is rotated so that the respective cranks extend horizontally. Themain bearing cap bolts are then used to secure, to the undersurface ofthe main bearing caps in depending relation therefrom, a pair ofsubstantially identical angle brackets apertured to receive these boltsand each having an aperture at its lower end, as secured to theundersurface of the main bearing caps. A pressing tool is thenpositioned in engagement with the lower end of the cylinder liner, andis connected by a threaded rod or bolt and a nut to a centering devicein engagement with the upper end of the cylinder liner. A cross bar isinserted through the aligned apertures of the two brackets, and anordinary shop type hydraulic jack is positioned on the cross bar withits upper end engaging the pressing tool. The jack is then extended topush the cylinder liner upwardly out of the cylinder. If

desired, exactly the same procedure may be utilized for inserting a newor reconditioned cylinder liner into the cylinder, although this isusually effected by a different technique.

The apparatus of the invention is very simple, and in addition to theknown pressing tool, includes the centering device and the threadedconnection between the centering device and the pressing tool. The mainelements of the apparatus include the two angle brackets for securementto the main bearing cap bolts, these brackets having longer amts formed,near their free ends, with a squareor rectangular aperture, and theseapertures receive a square or rectangular cross section relatively heavybar which supports the shop jack.

An object of the invention is to provide an improved method for removingcylinder liners of diesel engines used in automotive vehicles.

Another object of the invention is to provide such a method in which thecylinder liners are removed while the diesel engine remains mounted inposition on the vehicle. A further object of the invention is to providesuch a method in which the man hour requirements are only a minorfraction of the man hour requirements with present methods of removingcylinder liners from diesel engines. 1

Another object of the invention is to provide novel and simplifiedapparatus for removing cylinder liners from diesel engines, while thediesel engines remain mounted in automotive vehicles, and whichapparatus is cooperable with ordinarily used shop tools.

A further-object of the invention is to provide such an apparatus whichis simple, inexpensive, and easy to use.

Another object of the invention is to provide such an apparatus whichcan be used beneath the engine block of a diesel engine to removecylinder liners.

For an understanding of the principles of the invention, reference ismade to the following description of a typical embodiment thereof asillustrated in the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING In the Drawing:

FIG. 1 is a partial sectional view illustrating the apparatus of theinvention as operating to remove a cylinder liner from the cylinder of adiesel engine;

FIG. 2 is a sectional view taken on the line 2-2 of FIG. 1;

FIG. 3 is a sectional view taken on the line 3-3 of FIG. 1;

FIG. 4 is a top plan view of the pressing tool;

FIG. 5 is a bottom plan view 'of the centering disk; and

FIG. 6 is a view similar to FIG. 3 illustrating an alternativearrangement of the apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawing, theengine or cylinder block of the diesel engine, for use with automotivevehicles, is somewhat schematically illustrated at 10 as formed with acylinder 11 in which there is a cylinder liner 15. The undersurface ofblock 10 is formed with main bearing halves 12 receiving a crank shaft16 held in position by main bearing caps 17 secured to block 10 by bolts13 threaded into block 10. Shaft 16 has pairs of crank arms 14supporting journals 18 for the piston rods.

As is well known to those skilled in the art, such an engine block isformed with axially spaced main bearings, the main bearings beingdisposed between adjacent cylinders. The crank shaft 16 mounted thereinis formed with crank portions, including crank arms 14 and journals 18,connected, by connecting rods, to pistons which are slidable in linerssuch as 15. These liners are subject to wear and, after a predeterminednumber of hours of operation of the engine, it is necessary usually toremove a cylinder liner, or all the cyliner liners, and to replace thesame with new or rebuilt cylinder liners. Prior to the presentinvention, such removal of cylinder liners of diesel engines used inautomotive vehicles, such as trucks, buses and the like, could beeffected only by removing the entire engine from the vehicle, mountingan extraction apparatus on the top of the engine and pulling the lineror sleeve, such as 15, upwardly out of each cylinder, using what isknown as a pressing tool. The reason for this is that, as these enginesare mounted in vehicles, there is, above the engine, only sufficientspace for removal of the cylinder liner but insufficient space formounting of an extraction apparatus on top of the engine. As a result,up to the present time many man hours of work are required to remove andreplace thecylinder liners in automotive vehicle diesel engines, a goodpart of this time being required for removing the engine from thevehicle and replacing the engine in the vehicle.

With the method and apparatus of the present invention, the timerequired to remove and replace cylinder liners of an automotive vehiclediesel engine is reduced to a minor fraction of the time previouslyrequired. A major part of this reduction in man hours is due to the factthat the engine need not be removed from the vehicle, but can remain inplace thereon. The principal difference in the procedure using thepresent invention, as distinguished from the known procedures usedhitherto, is that the cylinder liner or sleeve 15 is pushed upwardly outof the cylinder rather than being pulled upwardly out of the cylinder,with all operations being performed from beneath the mounted engine.

For this purpose, the apparatus of the invention includes a pair ofsubstantially identical relatively heavy metal angle brackets 20,arranged to be secured to engine block by main bearing cap bolts 13, anda relatively heavy substantially rectangular or square cross section bar25 arranged to be supported by brackets 20 and to, in turn, support anordinary shop jack, such as the usual hydraulic jack found in most busgarages and the like. In addition, a pressure tool 30 is insertable intothe lower end of sleeve and is connected by a rod 27 to a centeringplate 35 seated in the upper end of sleeve 15. The upper or extensibleend of jack 26 is positioned in engagement with rod 27.

More particularly, the brackets comprise apertured angles 21 welded toflat straps 22, and the flat straps 22, adjacent their free ends, areformed with rectangular or square apertures or holes 23 therethrough.Cross bar 25 is cut to an appropriate length from solid rectangular orsquare cross section stock for insertion through apertures 23. Theapertures 19 in angles 21 have diameters substantially larger than thoseof the shanks of bolts 13, so as to have substantial clearancetherewith.

In a known manner, pressure tool is a segment of a circle centered onthe diameter, as best seen in FIG. 4, and includes curved ends 31 whichare circular arcs having a radius slightly less than the radius of theouter surface of liner 15. These circular arcs 31 are interconnected byparallel chords 32. The upper portion 33 of pressure tool 30 has itsarcuate ends also formed as circular arcs with a radius substantiallyequal to the radius of the inner surface of cylinder liner 15, so thatthis upper portion fits within the cylinder liner while the resultantlips 34 engage beneath the lower end of liner 15. Additionally, pressuretool 30 has a central aperture 36, and may have a slot extending fromthis aperture, as indicated in dotted lines in H6. 4.

Centering plate 35 includes a large diameter circular upper portion 37and a smaller diameter circular lower portion 38. Upper portion 37 has adiameter slightly less than the outer diameter of liner or sleeve 15,and lower portion 38 has a diameter substantially equal to the innerdiameter of liner or sleeve 15, so as to have a snug fit therein.Centering plate 35 is further formed with a central aperture 39 having aradial slot extending therefrom.

Rod 27 interconnects pressure tool 30 and centering plate 35, and has arelatively large cross section lower portion extending through aperture36 in pressure tool 30 and a threaded upper portion 38 extending throughaperture 39 in centering plate 35 and secured thereto by a nut 39.Portion 27 has an annular shoulder 24 seating against the undersurfaceof tool 30, and its lower end seats on the extensible member of jack 26.

In using the apparatus of the invention to perform the invention methodin removing liner 15 from cylinder 11, the appropriate cylinder head orheads are removed from block 10, the usual oil pan is removed from thebottom of block 10, the bolts 13 withdrawn from the block 10, andbearing cap 17 and crank shaft 16 is rotated so that a respectivejournal 18 lies in a horizontal plane. Bearing caps 17 remain in placedue to their wedging fit in block 10. Thereafter, angle brackets 20 aresecured by bolts 13 against the undersides of caps 17, the bolts 13being inserted loosely through the larger diameter apertures in angles21 and through the apertures in bearing caps 17, and threaded into block10. This holds brackets 20 suspended from bolts 13. Cross bar 25 is theninserted through the aligned rectangular or square apertures 23.

Meanwhile, centering plate 35 is positioned on the upper end of liner 15and pressure tool 30 is seated in the lower end of liner 15 andconnected to centering plate 35 by the rod 27 inserted through aperture36 to engage shoulder 24 with tool 30, and nut 29 threaded on rodportion 28 extending through aperture 39 in plate 35. An ordinary shophydraulic jack 26 then has its base positioned on cross bar 25 and itsextensible end is engaged with the lower end of rod 27. Jack 26 is thenextended to push sleeve or liner 15 upwardly out of cylinder 11. Ifdesired, essentially the same procedure may be used for re-inserting areconditioned or new cylinder liner into cylinder 11, although newliners usually are inserted into the cylinder by first shrinking theliner by chilling and then sliding it into the cylinder to expand bywarming to ambient temperature.

As mentioned, apertures 19 have substantial clearance with bolts 13.This permits brackets 20 to be used either in the manner shown in FIGS.1, 2 and 3, in which each bracket depends from a single respective cap13, or in the manner shown in FIG. 6, in which both brackets extendbetween adjacent caps 17.

The apparatus of the invention has the very pronounced advantage thatthe number of man hours required for changing the cylinder liners of adiesel engine are reduced to a minor fraction of those hitherto requiredby virtue of the fact that the engine remains in position on thevehicle. Furthermore, as a pusher type operation is utilized, ratherthan a puller type operation, the apparatus can be much more compact andmuch more simply handled. Additionally, the several parts of theapparatus, additional to those parts usually found in maintenancegarages, are simple and inexpensive to construct and capable of longlife.

While a specific embodiment of the invention has been shown anddescribed in detail to illustrate the application of the principles ofthe invention, it will be understood that the invention may be embodiedotherwise without departing from such principles. 4

What is claimed is:

1. A method of removing cylinder liners of diesel engines of automotivevehicles comprising the steps of, with the engine remaining mounted inthe vehicle,

removing a cylinder head; withdrawing the piston and connecting rod fromthe cylinder; rotating the crank shaft to position a respective crank toextend to one side;utilizing the main bearing bolts of the engine tosecure, to the main bearing'caps of the engine in depending relationtherefrom, a pair of substantially identical brackets; positioning apressing tool in engagement with the lower end of a cylinder liner;supporting a jack on the brackets in engagement with the pressing tool;and extending the jack to push the cylinder liner upwardly out of thecylinder.

2. A method of removing cylinder liners of diesel engines, as claimed inclaim 1, including the step of inserting a cross rod through alignedapertures in the lower ends of the brackets; and supporting the jack onthe cross rod.

3. A method of removing cylinder liners of diesel engines, as claimed inclaim 1, including providing centering means engaged with the upper endof the cylinder liner, and connecting the centering means to thepressing tool.

4. Apparatus for removing cylinder liners of diesel engines ofautomotive vehicles, with the engine remaining mounted in the vehicle,comprising, in combination, a pair of substantially identical bracketsconstructed and arranged for securement in depending relation to themain bearing caps of the engine by the main bearing bolts of the engineafter extraction of the piston and connecting rod; support meansengageable with said brackets in the mounted position of the latter; apressing tool seated on the lower end of the cylinder liner; and a jackseated on said support means and engageable with said pressing tool;whereby said jack can be extended to push the cylinder liner upwardlyout of the cylinder.

5. Apparatus for removing cylinder liners of diesel engines, as claimedin claim 4, in which said brackets are angle brackets includingrelatively short legs apertured to receive the main bearing bolts, anddepending relatively longer legs receiving said support means.

6. Apparatus for removing cylinder liners of diesel sr saaaasmat eatertr rstifia'sisass their free ends; said support means comprising a rodinserted through the aligned apertures.

7. Apparatus for removing cylinder liners of diesel engines, as claimedin claim 6, in which said apertures in the longer legs of said anglebrackets are substantially rectangular, said rod constituting a crossbar having a substantially rectangular cross section.

8. Apparatus for removing cylinder liners of diesel engines, as claimedin claim 7, said pressure tool including centering means engaged withthe liner and engageable by the extendible end of the jack.

9. Apparatus for removing cylinder liners of diesel engines, as claimedin claim 8, in which said centering means includes a pressing diskhaving a circular portion with a conforming fit within the lower end ofa cylinder liner and a peripheral lip engageable with the lower end of acylinder liner.

10. Apparatus for removing cylinder liners from diesel engines, asclaimed in claim 9, in which said centering means further includes acentering disk having a circular portion with a conforming fit withinthe upper end of the cylinder liner and a peripheral lip engageable withthe upper end of the cylinder liner; and a rod extending between saidpressing disk and said centering disk, and having a threaded stemextending through an aperture in said centering disk for securementthereto by a nut.

1. A method of removing cylinder liners of diesel engines of automotivevehicles comprising the steps of, with the engine remaining mounted inthe vehicle, removing a cylinder head; withdrawing the piston andconnecting rod from the cylinder; rotating the crank shaft to position arespective crank to extend to one side; utilizing the main Bearing boltsof the engine to secure, to the main bearing caps of the engine independing relation therefrom, a pair of substantially identicalbrackets; positioning a pressing tool in engagement with the lower endof a cylinder liner; supporting a jack on the brackets in engagementwith the pressing tool; and extending the jack to push the cylinderliner upwardly out of the cylinder.
 2. A method of removing cylinderliners of diesel engines, as claimed in claim 1, including the step ofinserting a cross rod through aligned apertures in the lower ends of thebrackets; and supporting the jack on the cross rod.
 3. A method ofremoving cylinder liners of diesel engines, as claimed in claim 1,including providing centering means engaged with the upper end of thecylinder liner, and connecting the centering means to the pressing tool.4. Apparatus for removing cylinder liners of diesel engines ofautomotive vehicles, with the engine remaining mounted in the vehicle,comprising, in combination, a pair of substantially identical bracketsconstructed and arranged for securement in depending relation to themain bearing caps of the engine by the main bearing bolts of the engineafter extraction of the piston and connecting rod; support meansengageable with said brackets in the mounted position of the latter; apressing tool seated on the lower end of the cylinder liner; and a jackseated on said support means and engageable with said pressing tool;whereby said jack can be extended to push the cylinder liner upwardlyout of the cylinder.
 5. Apparatus for removing cylinder liners of dieselengines, as claimed in claim 4, in which said brackets are anglebrackets including relatively short legs apertured to receive the mainbearing bolts, and depending relatively longer legs receiving saidsupport means.
 6. Apparatus for removing cylinder liners of dieselengines, as claimed in claim 5, in which the longer legs of saidbrackets are formed with apertures adjacent their free ends; saidsupport means comprising a rod inserted through the aligned apertures.7. Apparatus for removing cylinder liners of diesel engines, as claimedin claim 6, in which said apertures in the longer legs of said anglebrackets are substantially rectangular, said rod constituting a crossbar having a substantially rectangular cross section.
 8. Apparatus forremoving cylinder liners of diesel engines, as claimed in claim 7, saidpressure tool including centering means engaged with the liner andengageable by the extendible end of the jack.
 9. Apparatus for removingcylinder liners of diesel engines, as claimed in claim 8, in which saidcentering means includes a pressing disk having a circular portion witha conforming fit within the lower end of a cylinder liner and aperipheral lip engageable with the lower end of a cylinder liner. 10.Apparatus for removing cylinder liners from diesel engines, as claimedin claim 9, in which said centering means further includes a centeringdisk having a circular portion with a conforming fit within the upperend of the cylinder liner and a peripheral lip engageable with the upperend of the cylinder liner; and a rod extending between said pressingdisk and said centering disk, and having a threaded stem extendingthrough an aperture in said centering disk for securement thereto by anut.